using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows.Data;
using System.Windows.Media.Imaging;
using System.Windows;

namespace AppToolkit.WPF.Services.UserMessageHandling.UI
{
    /// <summary>
    /// Inverts numeric value for visualization purposes.
    /// </summary>
    public class NegateConverter : IValueConverter
    {
        #region IValueConverter Members

        /// <summary>
        /// Converts a value. 
        /// </summary>
        /// <returns>
        /// A converted value. If the method returns null, the valid null value is used.
        /// </returns>
        /// <param name="value">The value produced by the binding source.</param><param name="targetType">The type of the binding target property.</param><param name="parameter">The converter parameter to use.</param><param name="culture">The culture to use in the converter.</param>
        public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            if (value is double)
                return -(double)value;

            if (value is int)
                return -(int)value;

            if (value is float)
                return -(float)value;

            if (value is decimal)
                return -(decimal)value;

            return DependencyProperty.UnsetValue;
        }

        /// <summary>
        /// Converts a value. 
        /// </summary>
        /// <returns>
        /// A converted value. If the method returns null, the valid null value is used.
        /// </returns>
        /// <param name="value">The value that is produced by the binding target.</param><param name="targetType">The type to convert to.</param><param name="parameter">The converter parameter to use.</param><param name="culture">The culture to use in the converter.</param>
        public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            if (value is double)
                return -(double)value;

            if (value is int)
                return -(int)value;

            if (value is float)
                return -(float)value;

            if (value is decimal)
                return -(decimal)value;

            return DependencyProperty.UnsetValue;
        }

        #endregion
    }
}
